A game which trains the brain to avoid unhealthy food such as cakes, biscuits and chocolate can lead to ‘pain free’ weight loss and cut energy intake by more than 200 calories a day, scientists have said.

Psychologists at the University of Exeter showed that less than ten minutes a day of ‘brain training’ using a game which takes away the ‘mental reward’ of sugary and fatty foods, reduces calorie intake.

Professor Natalia Lawrence’s Food Trainer app is free and is being launched this week on Android devices.

It is based on neuroscience research which suggests people are more inclined to choose fatty and sugary foods because they activate the brain’s reward system, stimulating the release of dopamine and endorphins, which can produce feelings of pleasure and make the person want more.

Prof Natalia Lawrence

The game works by flashing up pictures of healthy and unhealthy food and the user has to react by only pressing on the healthy foods to score points. The simple act of ignoring unhealthy foods, and stimulating the reward response to healthy foods is enough to retrain the brain into craving healthier options, say scientists.

A study of 83 adults showed that people who played the game online just four times in one week lost weight and ate an average of 220 kcal less per day – roughly equivalent to a chocolate-iced doughnut.

“It’s very exciting to see that our free and simple training can change eating habits and have a positive impact on some people’s lives,” said Dr Lawrence.

“In an age where unhealthy food is so abundant and easily available and obesity is a growing health crisis, we need to design innovative ways to support people to live more healthily.

“We are optimistic that the way this app is devised will actually encourage people to opt for healthy food such as fruit and vegetables rather than junk food.”

Studio manager Fiona Furness was one of the first to trial the game and has lost two stone in weight so far, dropping from 11 stone to nine stone.

Mrs Furness, who is in her 50s, said the “pounds just melted way.”

“The results have been remarkable,” she said.

“I used to feel really guilty about my bad snacking habits. I’d often be rushing about, and I’d grab something high calorie and unsatisfying – often a packet of crisps. I’d be hungry again really soon afterwards so it became a vicious cycle.

“These days, if I am feeling peckish I’ll go for a banana or a pack of almonds. That’s the food I’m craving. I’m now closer to nine stone than 11 – the pounds just melted away over eight or nine months without me even noticing.

“The weight loss wasn’t really my goal though – I feel younger and more energetic. Perhaps I’m particularly susceptible to this kind of brain training, but it has been transformative for me.”

Nearly two thirds of adults in Britain are overweight or obese, and the UK is forecast to be the fattest country in Europe within 10 years

Users of the app, who should ideally use it for a few minutes a day without distractions, can tailor it to reduce compulsions to unhealthy food they have most problem with, as well as alcohol, but not to reduce consumption of healthy foods including vegetables.

The scientists have launched a crowd-funding campaign to raise up to £5,000 to develop the app, this week made available for Android devices, into an app that can be used on iPhones and iPads.